# NTSB GAA16CA042: Cessna 421, N19CH, Amarillo, TX, October 14, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: October 14, 2015, 13:45 local (18:45 UTC) - Place: Amarillo, TX - Coordinates: 35.08139, -101.755836 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.0814&lon=-101.7558&mi=10 - Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping) - Defining event: [Taxi-to runway: Ground collision](https://openairdocs.org/ntsb-events/200) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 5, 2016 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: Federal Aviation Administration - NTSB case key (mKey): 92290 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA16CA042 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/92290/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=92290 - Page: https://openairdocs.org/ntsb/GAA16CA042 ## Probable cause The loss of directional control during taxi to the runway as a result of insufficient brake fluid level in the right brake master cylinder, resulting in a taxiway excursion and collision with a drainage culvert. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: brake](https://openairdocs.org/ntsb-findings/01023242): Aircraft › Aircraft systems · Inoperative (probable cause); cases with it: [Cessna 421B, 1 case](https://openairdocs.org/ntsb-findings/01023242/cases.md?model=2076014), [All aircraft, 297 cases](https://openairdocs.org/ntsb-findings/01023242/cases.md) - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Cessna 421B, 3 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=2076014), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) - [Fluids](https://openairdocs.org/ntsb-findings/01071000): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Cessna 421B, 1 case](https://openairdocs.org/ntsb-findings/01071000/cases.md?model=2076014), [All aircraft, 11 cases](https://openairdocs.org/ntsb-findings/01071000/cases.md) - [Landing gear system: brake](https://openairdocs.org/ntsb-findings/01023242): Aircraft › Aircraft systems · Not serviced/maintained; cases with it: [Cessna 421B, 1 case](https://openairdocs.org/ntsb-findings/01023242/cases.md?model=2076014), [All aircraft, 297 cases](https://openairdocs.org/ntsb-findings/01023242/cases.md) - [Maintenance: scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010): Personnel issues › Task performance · Maintenance personnel; cases with it: [Cessna 421B, 2 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md?model=2076014), [All aircraft, 320 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Instructor/check pilot; cases with it: [Cessna 421B, 11 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=2076014), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Object/animal/substance](https://openairdocs.org/ntsb-findings/03022000): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Cessna 421B, 1 case](https://openairdocs.org/ntsb-findings/03022000/cases.md?model=2076014), [All aircraft, 224 cases](https://openairdocs.org/ntsb-findings/03022000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Taxi-to runway: Loss of control on ground](https://openairdocs.org/ntsb-events/230); cases with it: [Cessna 421B, 3 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=2076014), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Taxi-to runway: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Cessna 421B, 7 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=2076014), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) - [Taxi-to runway: Ground collision](https://openairdocs.org/ntsb-events/200) (defining event); cases with it: [Cessna 421B, 2 cases](https://openairdocs.org/ntsb-events/200/sequence.md?model=2076014), [All aircraft, 618 cases](https://openairdocs.org/ntsb-events/200/sequence.md) ## Analysis According to the flight instructor, during the taxi to the runway, the pilot receiving instruction stated that he did not have authority in the right brake. The flight instructor reported that he too applied pressure to the right brake to no avail. He reported that the airplane exited the runway to the left, impacted a drainage culvert and the left main landing gear collapsed. The airplane sustained substantial damage to the left wing spar. The airplane brake system was examined by the operator's Director of Maintenance, who determined that the right brake master cylinder was low on fluid causing the brakes to be weak. The last maintenance performed on the brakes occurred on 7/8/2015 at which time both brake discs were replaced and all the brake pads were replaced. The total time on the airplane since the last maintenance on the brakes was 33.6 hours. ## Factual narrative According to the flight instructor, during the taxi to the runway, the pilot receiving instruction stated that he did not have authority in the right brake. The flight instructor reported that he too applied pressure to the right brake to no avail. He reported that the airplane exited the runway to the left, impacted a drainage culvert and the left main landing gear collapsed. The airplane sustained substantial damage to the left wing spar. The airplane brake system was examined by the operator's Director of Maintenance, who determined that the right brake master cylinder was low on fluid causing the brakes to be weak. The last maintenance performed on the brakes occurred on 7/8/2015 at which time both brake discs were replaced and all the brake pads were replaced. The total time on the airplane since the last maintenance on the brakes was 33.6 hours. ## Aircraft - Registration: [N19CH](https://openairdocs.org/deregistered/N19CH-2016-06-21), registration cancelled 2016-06-21, S/N 421B0462, built 1973 (OpenAirDocs) - Reported make and model: CESSNA 421 (B) - Registry model: [Cessna 421B](https://openairdocs.org/model/cessna-421b) (registry code 2076014) (OpenAirDocs) - Registry engine: [Continental GTSIO-520-C](https://openairdocs.org/engine/continental-gtsio-520-c) (registry code 17035, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 421B0462 - Year built: 1973 - Airframe hours: 4525.1 - Engines: CONT MOTOR GTSIO-520-H 375 horsepower reciprocating; CONT MOTOR GTSIO-520-C 340 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Denny Ohara, doing business as First Flight - Registered owner: Ohara Aviation Management Services Lc - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, April 15, 2015 - Departed: H81, Amarillo, TX - Destination: H81, Amarillo, TX - Airport: H81, River Falls, runway 17, 6,015 × 60 ft, asphalt - Equipment: Stall warning system, Onboard weather, Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 68; injuries: none; flight instructor, airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review June 26, 2015; seat: right; restraint: 3-point; flight hours: 32,000 total, 4,000 in this make and model, 32,000 as pilot in command, 24 in the last 90 days, 12 in the last 30 days - Pilot; age 26; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2; last flight review December 31, 2014; seat: left; restraint: 3-point; flight hours: 1,620 total, 38 in this make and model, 1,500 as pilot in command, 146 in the last 90 days, 73 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 13 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 88 °F, dew point 45 °F - Altimeter: 30.12 inHg - Observed at: KAMA, 1 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20151014018329A](https://openairdocs.org/incident/20151014018329A), Oct 14, 2015: Cessna 421B, Amarillo, TX, Substantial damage. On October 14, 2015 on or ABOUT14:30 local time, a Cessna 421-B aircraft was on a training flight; while taxiing for takeoff at River Falls Airport (81XA) in… ## Docket (3 files) The files NTSB released with the investigation on October 27, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=92290. 3.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436465&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Director of Maintenance (Brake Inspection) (item 2, .PDF, 59 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436466&FileExtension=.PDF&FileName=Director%20of%20Maintenance%20(Brake%20Inspection)-Master.PDF - Photo (item 3, .PDF, 230 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436467&FileExtension=.PDF&FileName=Photo-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.